Find the best run in an MLflow experiment by a given metric, supporting names like 'accuracy' or 'loss' and special characters such as '/'. Set ascending to true for lower-is-better metrics.
Get the best run by a specific metric (e.g., highest accuracy, lowest loss). Works with metrics containing special characters like '/' (e.g., 'trading/total_profit')
| Name | Required | Description | Default |
|---|---|---|---|
| metric | Yes | ||
| ascending | No | ||
| experiment_id | Yes |
Changes observed during successful MCP inspections.
v0.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=true, consistent with 'Get'. Description adds useful context about metric names with special characters, which is not in annotations. However, lacks details on edge cases (e.g., no runs, ties).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two concise sentences, front-loaded with purpose, second sentence adds an edge case. No redundancy or unnecessary words.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
No output schema, and description does not specify return format or behavior in ambiguous cases (ties, missing metric). Adequate for basic use but incomplete for complex scenarios.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 0%, but description only explains the 'metric' parameter with an example. 'experiment_id' and 'ascending' are not elaborated, leaving the agent underinformed about required inputs.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Clearly states the tool retrieves the best run by a specific metric, distinguishing it from siblings like 'get_run' and 'get_runs'. Also notes handling of special characters in metric names, adding specificity.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Provides a clear use case (getting best run by metric), but does not explicitly state when to avoid this tool or contrast with alternatives like 'get_run_metrics' or filtering.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.